User Support Level 2

Note	The features and/or parameters listed in this article may not be available from your telephone service provider.

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Introduction

The supporter finds here instructions how to handle a user's level 2 telephony problems:

• Best Practice for Handling an User Problem
• Record the Customer's Data and Problem Description
• Analyzing the Customer Problem
• Solving the Customer Problem

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Introduction Support Level 2

The level 2 support is the first instance where the user's telephony problems are handled that a user cannot solve himself. Additionally the level 2 supporter must be able to detect if the user problem is a "single" problem or if there is a large scale problem, that produces the same problem for multiple customers, e.g. data transfer problems in the Internet so that no VoIP call signaling is possible.

The level 2 supporter must be aware of the complexity of a VoIP system and the multitude of telephony solutions on the user side. Further he needs an understanding of:

• IP networking
• VoIP protocols SIP for signaling, SDP and RTP for speech transmission.

Overview of a VoIP system and the multitude of user telephony solutions:

The level 2 supporter faces problems with the following layers:

1. Equipment
2. IP data transfer
3. Telephony service

And each of this layer can be located into the following raw areas:

1. Customer/User site
2. Internet Service Provider ISP
3. Telephony Provider

This layer and dividing into areas produces a "3x3 Support Matrix":

Within this "3x3 Support Matrix" the supporter can:

• advice the customer what to do when the problem is located in the nodes 1-T, 1-D and 1-E
• check the customer configurations on the VoIP Switch, node 3-T, and, if he has operator rights, adjust configurations.

For the other cases the level 2 supporter must be able to identify if:

• the user must contact his ISP, due to possible Internet access problems
• the VoIP System administrator must be involved, due to possible telephony service problems

Hint:

These cases indicate mostly large scale problems within the VoIP system!

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Best Practice for Handling an User Problem

Best Practice

Record the customer's data and problem description: Get the customer data Get the problem description from the customer Show me how ...   Cross check the user input against the VoIP switch configuration and logs. Via ConfigCenter check the users account configuration: Telephone number registration TopStop RuleSet Consult the "Call Data" for the last connection attempts and connections longer than 2min Show me how ...   Evaluate the user's VoIP setup: For questioning and analyzing the user's problem it is necessary that the supporter is aware of the VoIP setup of the user. Show me how ...   Check the big picture: If you are sure that the problem is "single" one continue with the next step "Solve the customer problem" If you suspect that the customer is not the only one with this problem within a short time range, e.g. 30min, then contact the VoIP switch administrator/operator if there is known issue in the VoIP system that causes this type of problem. Show me how ...   Solve the customer's problem: You have now enough basic information for solving the customer's problem Show me how ...   If you are not able to solve this problem then contact the provider support. Have ready all collected information and what you have done and found out until now.

The supporter shall record the user information and the results of his own research:

This information is most welcome if he needs the support of the provider and has to inform him about the case.

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Step 1: Record the Customer's Data and Problem Description

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Get the Customer's Data

From the customer get:

• Name of the caller
• Telephone number of the caller
• if applicable the company name

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Note the Customer's Problem Description

From the customer get:

• Date and time of the issue
• The involved telephone numbers
• The problem description

If the customer doesn't know then identify via the ConfigCenter the telephone number and its associated account.

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Step 2: Cross Check the User Inputs

With this cross check the supporter can validate the user information, gets an impression of the state of the account and will probably find the reason for the user problem...

Via ConfigCenter check the users status and account configuration on the VoIP Switch:

1. Check "Validity":

   Check if the user account and its addresses are existing and "valid".

2. Check the telephone number registration status.

   If there is no registration you can proceed directly with The user device is not registered ...

3. Check "TopStop":

   Check if a TopStop in the account or address prevents the user from doing outgoing calls.

4. Check "RuleSet":

   Check if a RuleSet in the account or address prevents the user from doing outgoing or receiving calls.

5. Check "Call Forwards" or "Call Rejecting":

   Check if a "Call Forwards" or "Call Rejecting" in the account prevents the user from doing outgoing or receiving calls.

6. Check "Call Data":

   Consult the "Call Data" for the last connection attempts and connections longer than 2min of the user.

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Step 3: Evaluate the User's VoIP Setup

For questioning and analyzing the user's problem it is necessary that the supporter is aware of the VoIP setup of the user.

The experienced supporter knows of the user's VoIP setup after the cross check . If not here the supporter finds the most implemented VoIP setup's.

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VoIP Setup: Residential

Characteristics:

• Private household
• Single or few telephone number
• Each telephone number registers individually

Most common problems:

• Account or telephone number blocked on the VoIP switch
• Telephone number not correctly ported to the telephony provider
• Telephone not correctly configured
• Telephone, cables defect
• Internet access fails

Overview VoIP Setup:

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VoIP Setup: Legacy ISDN PBX

Characteristics:

• Company PBX
• The ISDN PBX is connected via BRI or PRI to an ISDN-SIP Gateway
• One or more telephone number ranges
• The telephone numbers are registered via a main number
• The telephone number of incoming calls are signaled with only a few digits

Most common problems:

• Account or telephone numbers blocked on the VoIP switch
• Telephone number ranges not correctly ported to the telephony provider
• Wrong incoming telephone number signaling
• Internet access fails
• The company Firewall VoIP ALG interferes with the SIP signaling or needed IP ports are blocked.
• QoS problems for speech, Fax, DECT

Overview VoIP Setup:

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VoIP Setup: IP PBX

Characteristics:

• Company PBX
• The IP PBX is connected directly or via SBC to the VoIP Switch
• One or more telephone number ranges
• The telephone numbers are registered via a main number

Most common problems:

• Account or telephone numbers blocked on the VoIP switch
• Telephone number ranges not correctly ported to the telephony provider
• The company Firewall and/or SBC VoIP ALG interferes with the SIP signaling or needed IP ports are blocked.
• Internet access fails
• QoS problems for speech

Overview VoIP Setup:

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VoIP Setup: vPBX

Characteristics:

• Company PBX
• The IP Phones are connected directly to the VoIP Switch
• One or more telephone number ranges

Most common problems:

• Public account and/or public telephone numbers blocked on the VoIP switch
• Public telephone number ranges not correctly ported to the telephony provider
• Private account and/or private telephone numbers blocked on the VoIP switch
• Provisioning of the SIP devices out of the AdminCenter
• The company or home office Firewalls and/or SBCs VoIP policies or ALG interferes with the SIP signaling or needed IP ports are blocked.
• Company/home office Internet access fails
• QoS problems for speech, FAX, DECT

Overview VoIP Setup:

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Step 4: Check the Big Picture

At this point the supporter should get aware if the problem is limited to this user or if it could be large scale problem within the VoIP System.

If the supporter suspects a large scale problem, due to a great amount of the same ore similar user complains then he should contact the telephony provider support or emergency organization.

If the supporter has enough privileges he can check:

1. The VoIP Switch component status

   This will show if the VoIP Switch itself hat a problem.

2. The VoIP System monitor

   Here you can check if:

   • The registrations dropped in a large scale
   • The calls dropped in a large scale
   • The IP connectivity somewhere in the VoIP system failled

At any rate the supporter must inform the VoIP system administrator!

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Step 5: Solve the Customer Problem

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Solve "Device / Network / Configuration / Registration" Problems

This problem type covers the following erroneous conditions:

• The device doesn't start
• The device doesn't integrate into the IP network
• The device is not correctly configured
• The device doesn't register at the VoIP Switch

1 Check: Review the account and telephone number configuration

	Customer	Internet ISP	Telephony Provider
Telephony			Check via ConfigCenter: Does the user account exist and is it "valid"? Does the telephone number exist and is it "valid"? Actions: → Check why the account, telephone number doesn't exist or is disabled → activate them if allowed.
Data Transfer
Equipment

2 Check: Where REGISTER messages received from the device on the VoIP Switch?

	Customer	Internet ISP	Telephony Provider
Telephony			In the "Support Log" search for the device registration in the present and past time. Set the "Support Log" filters Insert at "Text" the account name Insert at "From" - "Until" a reasonable time span where registrations could be expected Select the category: "Registration" Start the search and find out according the results what is going wrong. If needed repeat the search with the telephone number in the "Text" or other time spans
Data Transfer
Equipment

Failed registrations due to disabled account or address:

2017-09-15-07:56:49.553 Registration failed, disabled account aan1-00093 tried to register number 0449980010

Actions:

• Check why the account is disabled and activate if allowed.

Failed registrations due to wrong SIP credentials:

2017-09-15-08:05:38.117 Registration failed, invalid credentials for account acc-01 2017-09-15-08:05:39.112 Registration failed, unknown username 'myusername' tried to register '0123456789' 2017-09-15-08:05:38.377 Registration failed, unknown number '0987654321' tried to register for account acc-01

Actions:

• The user must manually adjust the SIP credentials on the device
• The user must re-configure the device via AdminCenter

The device didn't refresh its registration:

2017-09-15-07:59:00.862 RegID989961 ended for 0987654321 ip=111.111.111.111:65398 ua=my-device v1.0

Actions:

• Order the user to check if the device is really on-line!
• Order the user to check if the device is defect? powered on? patch? IP address? → see below

For information a successful registration:

2017-09-15-07:59:30.383 RegID989965 started for 0987654321 ip=111.111.111.111:65398 ua=my-device v1.0

Hint:
The supporter might try to find REGISTER messages from the device in the "Trace" . This gives the certainty that the message was received by the VoIP switch. The supporter can filter for the telephone number. If the IP address is needed then the customer must be able to tell or evaluate it, e.g.:

https://www.whatismyip.com/

3 Check: Is the device correctly configured for registration?

	Customer	Internet ISP	Telephony Provider
Telephony	For a manually configured device, check that the device has the correct configuration for: Telephone number SIP credentials VoIP Switch domain configuration Actions: → The user must manually check the device configuration and if needed adjust its configuration of the telephone number, SIP credentials and VoIP Switch domain for registration For a automatically via AdminCenter configured device check that: the selected device type in the AdminCenter is identical to the physical one. Actions: → If not the same type then the user must re-configure the device via AdminCenter For a automatically via AdminCenter configured device check that: the user device has downloaded its configuration. Actions: → If the configuration is not downloaded then it must be checked if the device: has got an IP address in the local IP network has access to the Internet has access to the configuration download of the Telephony Provider. By default this is the IP address of the VoIP Switch domain and uses the protocol HTTPS on TCP port 443. Check with the Telephone provider or via ConfigCenter > Menu "System" > "Zone Profiles" → The user must check if the Firewall, SBC or Access Router doesn't block HTTPS traffic to and from the configuration download of the Telephony Provider
Data Transfer
Equipment

4 Check: Is the device powered on, not defect and connected to the IP network?

	Customer	Internet ISP	Telephony Provider
Telephony
Data Transfer
Equipment	Check if the device correctly powered and shows basic activity? Is the power cable correctly plugged in? Is the power cable Does the device show power on indication, e.g. display on, LED on? Actions: → replace the power cable → replace defect device if the powering is ok but no working indication is displayed

Warning

Defect power cables must be replaced! Faulty power cables can be life-threatening!

	Customer	Internet ISP	Telephony Provider
Telephony
Data Transfer
Equipment	Is the device correctly connected to the IP network? Are there LED flashing or glow next to the network plug on the device or at the peer device (access router, IP switch)? The user must check the patch cable and if it is correctly plugged in Actions: → replace the patch cable → plug in the patch cable at a different port at the peer device (access router, IP switch)

5 Check: Has the device an IP address and can access the Internet?

	Customer	Internet ISP	Telephony Provider
Telephony
Data Transfer	Has the device got an IP address? Check on the device if it has received an IP address, e.g. via display or maintenance GUI. Actions: If no IP address was assigned the user must: → Check if the device is really connected to the IP network → if the DHCP service in the IP network is running If the user cannot check the DHCP service he must contact the company IT responsible or the responsible of maintaining the access router.
Equipment

Hint:
In the wake of this problem type a firmware upgrade of the device has to be considered too.

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Solve Problem: Telephone Connections

This problem type covers the following erroneous conditions:

• Incoming or outgoing calls are not working
• Wrong called number
• Call supervision
• User device not registered
• User device not correct configured
• SIP signaling in general

1 Check: Review the account and telephone number configuration / registration

	Customer	Internet ISP	Telephony Provider
Telephony			Do this check for the A and/or B telephone number if they are on-net numbers of the VoIP SWitch. Check via ConfigCenter: Does the telephone number exist? Is the telephone number valid? Is the user account valid? Is the telephone number correctly registered Actions: → Check why the account, telephone number doesn't exist or is disabled and activate if allowed. → Check why the device is not registered at the VoIP Switch
Data Transfer
Equipment

Hint:

• If the device is not registered outgoing calls might be working but NO incoming call will work.

2 Check: Was the called number correctly transmitted to the peer?

	Customer	Internet ISP	Telephony Provider
Telephony			Check via ConfigCenter: In the "Call Data" search for the erroneous call: Set the "Call Data" filters: Insert at "Time" a reasonable time span where the erroneous call is to be expected. Set "Duration" to 00:00:00 Insert at "Called Number" the called number Start the search and identify the CDR of the erroneous call in the list If no CDR was found search for the "Calling Number"! Open the identified CDR and get the trace of the call, click the Button [ Trace ] Check if the called number in the "TO-Header" in all INVITE messages is correct: Is the called number correct? Often the users don't dial all digits or wrong digits or the configured number on a direct call key is incorrect. If the number is dialed correctly then it can be that the destination is not reachable. Outgoing calls from a vPBX can miss the public prefix Check the peers call cancel reason: SIP Failure Responses Actions: → Inform the user to dial the correct number. → Try to reach the called number via an alternative telephone network, e.g. from a mobile telephone. → Check with the support of the telephony provider why the called number is not reachable.
Data Transfer
Equipment

3 Check: What is the reason of an interrupted connection?

	Customer	Internet ISP	Telephony Provider
Telephony	Search in the "Call Data" for the erroneous call: Set the "Call Data" filters: Insert at "Time" a reasonable time span where the erroneous call is to be expected. Set "Duration" to 00:00:00 Insert at "Called Number" the called number Start the search and identify the CDR of the erroneous call in the list If no CDR was found search for the "Calling Number"! Open the identified CDR and check for the interruption reason: Was the connection released by a peer, A or B side? Check cancel reason in "State" ( SIP Failure Responses ) Actions: → Inform the user about the release reason, e.g. his own device or the peer device released the call regularly (but probably nor expected). Check if a call was released due to call supervision: Variant 1: Session Timer was not refreshed: Open the "Trace" of the connection and check if the connection was released due to missing RE-INVITE from the peers when the Session Timer run out. Variant 2: SIP INFO were not answered by the peer: Open the "Trace" of the connection and check if the connection was released due to not answered INFO messages that were sent from the VoIP Switch toward the peers. If activated the INFO's are sent usually every 120sec. Actions: → Inform the user that his device did not restart the Session Timer or did not answered INFO messages. The user must inspect the device configuration. Or the Variant 3: Missing RTP packets between the peers: Actions: → Inform the user about the release reason, e.g. his own device or the peer device released the call regularly (but probably nor expected). → Inform the user that his device did not restart the Session Timer or did not answered INFO messages. The user must inspect the device configuration. Or the
Data Transfer
Equipment

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Solve Problem: Disturbed Speech Transmission

Instruction how to solve disturbed speech transmission, e.g.:

• Short interruptions during the connection
• No transmission in one direction from the beginning of the connection
• No transmission in both directions from the beginning of the connection

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Solve Problem: Disturbed FAX Transmission

Instruction how to solve interrupted FAX transmission, e.g.:

• Fax transmission doesn't start
• Not all pages are transmitted

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Solve Problem: DECT Multi-Cell Handsets are not Working

Instruction how to solve problems with DECT Multi-Cell handsets, e.g.:

• Hand over from cell to cell not working
• Bad speech quality

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© Aarenet Inc 2018

Version: 3.0     Author:  Aarenet     Date: May 2017